1. F_4 = F_2[w]/(w^2+w+1): field axioms OK (0,1,w,w^2 = 0,1,2,3)
   PG(2,4): 21 points, 21 lines, 5 points per line, two points on exactly one line OK
2. generators invertible, preserve lines; |P| = 60480 = |PGL(3,4)|; |Q| = 2880; Q transitive on the other 20 points (P is 2-transitive) OK
3. phibar: homomorphism (checked for all g in Q against 5 generators of Q), image = Alt(5 lines), |ker| = 48, the 16 elements of order <= 2 in the kernel form a group (elations with centre 0) OK
4. |Q_t| = 192, 144, 240 for t of order 2, 3, 5; M = 240; |P|/M = 252 = 21 * 12; class sizes of T: [1, 12, 12, 15, 20]; MinSubDeg(H) = 12 OK
5. identical to the datum pgl3.tw_datum(4, 'PGL') used by the other scripts OK
ALL CHECKS PASSED
